385964 divided by 15 
The aim is to understand the frequency of 15 in 385964.

On to step 1:
15 can be fit into 3 0 times, resulting in a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 3 leaves us with 3.
Bring next digit (8) of the dividend behind the 3 and repeat the process: 38 / 15

Step 2:
If we divide 38 by 15, we get 2 and a remainder of 8.
The next digit of our result is 2. 
Result so far: 2.0
Deduct 30 from 38 and we're left with 8.
Grab the next digit (5) from the dividend, add it to 8, then carry on: 85 / 15

Advancing to step 3:
15 goes into 85 5 times with a remainder of 10.
Put 5 as the next digit of the answer. 
Result so far: 25.0
Deduct 75 from 85 and we're left with 10.
Append the next digit (9) from the dividend to 10 and continue with: 109 / 15

Moving on to step 4:
The number 15 fits into 109 7 times, leaving a remainder of 4.
The number 7 becomes the next digit in our result. 
Result so far: 257.0
Deduct 105 from 109 and we're left with 4.
Include the next digit (6) from the dividend after 4, then repeat: 46 / 15

On to step 5:
If we divide 46 by 15, we get 3 and a remainder of 1.
The number 3 becomes the next digit in our result. 
Result so far: 2573.0
Subtracting 45 from 46 leaves us with 1.
Take the next digit (4) from the dividend and append it to 1, then repeat: 14 / 15

Going ahead to step 6:
The number 15 fits into 14 0 times, leaving a remainder of 14.
Record the quotient 0 as the next digit in the result. 
Result so far: 25730.0
If we subtract 0 from 14, we get 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Advancing to step 7:
The number 15 fits into 140 9 times, leaving a remainder of 5.
The next digit of our result is 9. 
Result so far: 25730.9
If we subtract 135 from 140, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Moving on to step 8:
15 can be fit into 50 3 times, resulting in a remainder of 5.
The next digit of our result is 3. 
Result so far: 25730.93
Subtracting 45 from 50 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 9:
When dividing 50 by 15, we get 3 with a remainder of 5.
Record the quotient 3 as the next digit in the result. 
Result so far: 25730.933
Deduct 45 from 50 and we're left with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

The quotient of the division is 25730.933, and the remainder is 0.0005.